pycosat

library0.6.6pypypi✓ verified 88d ago

Python bindings to PicoSAT, a popular SAT solver written in C. Version 0.6.6 is the latest. The library is mature but receives infrequent updates; it is in maintenance mode.

data

pip install pycosat

github ↗package ↗

INSTALL

IMPORT

SIG · PYCOSAT

pycosat

datapythonv0.6.6

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

itersolve

✓ from pycosat import itersolve

✗ from pycosat import solve

itersolve is the generator version; solve is not a public function in pycosat.

Solve a simple CNF SAT problem using the generator itersolve.

import pycosat # Solve a SAT problem: each clause is a list of integers cnf = [[1, -2], [-1, 3], [-2, -3]] solution = pycosat.itersolve(cnf) for sol in solution: print(sol)

Debug

Known issues

deprecatedThe function `solve` is not available; use `itersolve` or `blocksolve`.

fix

Replace `pycosat.solve(...)` with `next(pycosat.itersolve(...))` for a single solution.

affects: >=0.6

breakingIn version 0.6.4, a memory leak was fixed in `blocksolve()`. If you rely on heavy iteration, upgrade to avoid cumulative memory usage.

fix

Upgrade to 0.6.4 or later: `pip install --upgrade pycosat`.

affects: <0.6.4

gotchapycosat only accepts DIMACS CNF format, not other SAT formats like DIMACS WCNF or OPB. Variables must be positive integers.

fix

Convert your problem to DIMACS CNF (list of lists of non-zero integers, no 0).

affects: all

Errors

Common errors & fixes

AttributeError: module 'pycosat' has no attribute 'solve'

pycosat does not expose a `solve` function; use `itersolve` or `blocksolve` instead.

fix

Use `next(pycosat.itersolve(cnf))` or `list(pycosat.itersolve(cnf))`.

MemoryError: Unable to allocate ...

pycosat uses the PicoSAT library which may allocate large arrays for huge CNF formulas. Also, a memory leak in versions <0.6.4 could cause OOM.

fix

Upgrade to 0.6.4+ and consider splitting the problem into smaller chunks.

Upgrade

Version history

0.6.6latest on PyPI · released Oct 3, 2023

Audit

Dependencies

No dependency data recorded yet.

Agent activity

6 hits · last 30 days

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Resources

githubhttps://github.com/ContinuumIO/pycosat ↗

packagehttps://pypi.org/project/pycosat/ ↗